Printing telegraph exchange system



Sept. 12, 1933.

D. B. PERRY PRINTING TELEGRAPH EXCHANGE SYSTEM Filed June 11, 1931 2 Sheets-Sheet l lNVE/VTOR 0. B. PERRY A TTOR/VEV Filed June 11-, 1951 2 Sheets-Sheet 2 EOFOI INVENTOR D. B. PERRY A TTORNEY Patented Sept. 12, 1933 7 PRINTING TELEGRAPH EXCHANGE SYSTEM Donald B. Perry, Maplewood, N. J., assignor" to Y American Telephone and Telegraph Company, a corporation of New York 7 Application June 11, losifserial No. 543,693

20 Claims.- (o1..1vs 4.1)

This invention relates to a switching arrangement f or connecting together signaling devices such as printing telegraph apparatus. The general object of this invention is to provide a radially extending transmission system which includes a central station, a number of outlying stations, and switching arrangements whereby anyoutlying station may transmit to or receive 'from the central station.

More specifically, an object of this invention is to provide a radial printing telegraph system or" the type described above, in which messages may be received at the central ofiice or atan outlying station in the absence of an attending operator.

The present invention is intended for use -by commercial establishments and police departments which have a central bureau of intelligence and anumber of offices distributed at surrounding points. In such systems the outlying stations communicate frequently with the central ofiice but seldom with each other. Transmission between the respective outlying stations andv the central office occursat irregular intervals. Consequently, the outlying station or the is to provide, in a signaling system, an arrange ment for connecting a calling party to an idle receiving device. A still furtherobject of this invention is to provide, in a system of the char-o act'er described, an. over-flow signal which becomes operative whenever an incoming call can notfind an idle receiving device, whereby an at tendant may establish a connectionibetwcen the incoming call and an additional receiving device. Still another object of the present invention is to simplify apparatus for routing an incoming call to an idle circuit.

Particular embodiments of the invention include a central oflice which is provided with a number of receiving printers adapted to be connected to a greater number of outlylngstations.

Associated with each receiving printer is agroup oi relays or a selecting device, according to'alternative embodiments of the invention. After a particular group 011' device has been actuated by an incoming call, it conditions the succeeding which the central office may send messages-to .trates, one embodiment of the present invention,

'3 respectively only, are shown; printers 4 and 5 with associated receivingequipthe desired station, the operation of the key group or device for establishing a connection with the next station to call. 7 I

The central ofiicemay also be provided with one or moretransmitting. devices, by means of. 6

. 0 any one of the outlying stations. A feature of the present invention is a signali g device to in.- fcrm the operator that a message is being re.- ceived from a particular station so that the operator doesnot attempt to transmit over the same 165 line. The outlying station mayreceive messages without an attending operator, due to remote oontrclarrangements for starting and stopping. the printer motor. j r L Figure 1 of the accompanyingdrawings illusanolFig. 2 is a modification thereof.

Description of apparatu sFig. 1

tions A and B, each of which outlying stations is provided with .a sending printer .41, receiving -39 printer iz motor 43, motor control relay 44 and key 45, by means of which; the outlying'station may establish a connection with" the central office-C. 1 r The central ofiice is provided with three receiving printers of which the line relays 1, 2 and two sending ment 4', 5; and a number of busylamps 6 and 7 corresponding to thejoutlying stations A :and '9 B. Includedalso in the centralroffice equipment are several groups ,of relays, the first group oomprisingrelaysll, 12 and 13 associatedwith receiving printer No. l, the second group coinprising relays ,21, 22,, 23 and 24 associated with 5 receiving printer No. 2; and the third group he operates the key 8 or 9 whichcorresponds :to

g PATENT OFFICE,

being either to the left or to the right, depend ing upon whether thesending printer 4 or the printer 5 is used. "Assume that the operator desires to transmitto station A by means of the sending printer 4. The key 8 is operated to the left. The operation of key 8 breaks a circuit which formerly extended from ground through 'motor control relay 51, normally operated contact 52 of key 8, conductor sending printer 4 and positive battery 55. The breaking of the latter circuit releases the armature of relay 51, thereby connecting the motor 57 to a generator 58 or other source of current. The motor com- -mences to rotate andcontinues rotating until the relay 51 is reenergized by restoration of the key 8 to its normal position.

Simultaneously with the startingof motor 57,

the sending printer 4 is connected in a series circuit with the sending and receiving printers of 'the outlying station A. The latter circuit may be traced as follows: Positive'battery 55, sending printer 4, conductor 53, normally nonoperated contact 61 of key 8, transmissicn line 7 62, receiving printer 42, sending printer 41 and ground. The closing of the uppermost contacts on the left side of key 8 closes a circuit for energizingthe motor control relay 44 at station A by the battery 64 at station C. The energization of relay 44 closes a circuit for starting the motor 43. The operator, by using the sending printer 4, may then transmit in the usual manner to the receiving printer 42 at the outlying station A.

' When the operator hasfinished transmitting she merely restores key 8 to normal thereby de- Distribution, of incoming calls At the central ofiice C incoming calls will be diverted automatically to an idle one of the receiving printers 1, 2 and 3. An idle-receiving printer may be selected and operated bythe calling station A or B without the aid of any operator at station C. Assume that a person 'at'station A desires to transmit a message to any idle one of the receiving printers 1, 2 and 3 at station C. The person at station A depresses the key which closes a circuit for energizing one of the relays 11, 21 or 31, whichever happens to be the first one in the order mentioned which is associated with an idle .printer. In case printer 1 is idle,.the relay 11 of the first group 7 will be energized in a circuit traced as follows:

Key 45, conductor 66, winding of relay 11, normally closed contacts 6'? of relay 11, lowermost armatures and contacts of relays 21 and 31, 're

spectively, conductor 69, inner right-hand arma ture of relay 13 and battery.

The'above described circuit through relay 11 could not have been clcsed had the relay 13 been energized prior to the closing of the key 45. The purpose of connecting relay 11 in a'circuit with 'a break contact of relay 13 is to ensure that relay 11 will not operate while its associated printer l is being used by a different calling-station, as will be explained more fully.

The energizing of relay 1.1 energizes relay 13 in a circuit including the lowermost armature and winding of relay 11, conductor 66 and key 45. The left-hand armature of relay 13 closes a circuit for operating relay 24 which connects battery 25 to the right-hand armatures of relay 23.

The inner upper armature of relay 11 in operating breaks a circuit normally connecting printer 1 and itsassociated motor control relay 70 in series. The breaking of this circuit releases the armature of the motor control relay '70 thereby starting the motor 71 for driving the receiving printer 1. The uppermost armature of relay 11' functions to start the motor at the calling station A by connecting the battery '73 throughthe key 8 and conductors 75 and 75 to the motor control relay 44. Relay is operated from the same battery and lights the busy lamp 6 associated with station A.

Simultaneously-with the starting of the inctors at the. calling and called stations relay 11 also serves to establish a connection between the sending and receiving printers 41 and 42 at station A and the printer 1 at station C. The connection between these printers may be traced in the following circuit: Ground, sending printer 41 and receiving printer 42 at station A, transmission line 62, normally operated contacts of key 8, conductor 62", make contact and inner upper armature of relay 11, conductor 76, break contact and inner upper armature of relay 12, conductor 77, receiving printer '1' and battery. The calling party at station A is automatically informed of the establishment of connection between the two printers by thestart-ing of motor 43. Having observed the rotation of this motor, the calling party types his message on the sending printer 41 in the usual'manner.

. The connection between the calling andthe called printers will be established as long as the key 45 remains depressed. When the key 45 is released, the circuit is broken through relay 11 which in turn releases relay 13, energizes relay '70 for stopping the motor 71, and disconnects battery from the motor control relay 44 thereby stopping the motor 43 at station A. Selecting the second printer Assume that while station A is transmitting to the receiving printer 1,-anincoming call is reofiice cannot be energized, because the circuit unoperated and the-conductor 166 remains connected to the winding of relay 22.

. Due to the energization of relay 13 and consequently of relay 24, battery is supplied to the right-hand armatures of relay 23. The relay 22 is there- -fore energized in a circuit traced as follows:

Ground, key 145, calling line 166, inner lower armature and contact of relay 12, winding and normally unoperated contacts 177 of relay 22, armature 183 of relay 32 right-hand armature of relay 23 and of relay 24 and battery 25. The

operation of relay 22 performs'functions similar tothose performed by the operation of relay 11 as before described. Relay 22 in energizing,

starts the motorl43 and the motor (not shown) for receiving printer 2. Relay 22 also connects calling printer 141, 142 with printer 2; energizes relay 23 to prevent any further connections to printer .2; lights the busy lamp 7: and disconnects the conductor 166 from the winding of relay 32. The manner in which the foregoing operations are performed will be understood by a comparison with. the above described operations performed by the relay 11.

It will be remembered that none of the second group of relays was affected bythe incoming call from station A when the first group and printer 1 were not in use. The reason is that a circuit could not be closed through the winding of relay 21 and an armature of relay 23 because the latter was disconnected from the battery 25. The battery connection was established after printer 1 became busy and the relay 13' ener gized.

Assume that station A is connected to printer 1, station B to printer 2 and that station A dis connects. The connection between station B through thesecond group of relays to printer 2 is not affected by the circumstancethat'the first group has become idle. .Although relay 13 broken at the lowermost armature of relay 22.

Overflow signal station A is depressed, none of the relays 11,

21 or 31 can be energized, and consequently line 66 will be connected in a closed circuit to ener- The closed circuit is gize relays 81 and 32. traced from ground, through key 45, conductor 66,. inner lower armatures' and contacts of .relays ll, 21 and 31, windings of relays 81 and 82, and armature of relay 83 to battery 87; Relay 82 energizes, closing a circuitthrough the winding of relay 85, which in turn operates and establishes a circuit through the winding of relay The latter breaks the circuit through the winding of relay 82 causing its release; The release of this relay is effective to release relay 85 and consequently relay 83. The circuit through the windings of relay 82 is then rees tablished and another cycle of operations is commenced. 'I'hiscycle of operation causes the circuit through relay 81 to be completed to bat- 'te'ry 87 through resistance'88 at one time and resistance 89 at another time and in the latter case relay 81 is shunted by relayf83. Resistance .89 is much higher than resistance 88 and its value is so chosen that relay 81 will release and reoperate once each cycle of operation of 32, 83, 85. H v y The alternate opening and closing of the circuit through the winding of relay 81 is effective to cause the-lamp 5 to flash on and 011. The attendant operator at thecentral office C is thereby'apprized of the circumstance that sta tion A which corresponds to lamp 6-is attempting to-connect to a receiving printer; but that all of the receiving printers are busy. The

, operator may manually. connect a spare. printer to the transmission line 62. Inasmuch as such connectionis established manuallyythe method of connecting the spare printer will be understood without further description, to those skilled in the art. One method is to employ one of the receiving equipments 4, 5' associated with the sending printers 4'01" 5 and make constations A and Bconnected to a central office C. The apparatus at the outlying stations A and B is similar to the apparatus at the stations. Aand B in Fig. 1, and is designated. by numerals increased'in each instance by 200 At the central ofiice C" there is a receiving printer,

201 associated with a bank. of selectors 210 and a similar printer 202 associated withv a similar bankof selectors 220. Each bank consists of five selectors S; T, TC,,M and L.: The function oi the selector switch S is tocontrol the steps ping of the selector switches in the entire bank.

The transfer switch Tserves to transfer an incoming call from the first bank. 210'to the next bank which may be the bank 220 or any inter.- mediate bani The transfer control switch TC cooperateswith the transfer switch T so that the incoming .call is connected through the ransfer switch T only when the selector switches of the bank 210 have reached a-posi-- tion corresponding to the calling station. The

, motor control switch M is adapted to start the motorat the calling station upon completion of the connection between the calling station and the receiving printer 201.

V The selector switch 1] servesto establish a connection between the printer at the callingstation and the receiving printer 201 associated with the bank 210.

Desc1'.i pt ion of operation-J75 2 The operation or" the circuit shown in Fig.2

.will be more'clearly understood by assuming that i the calling party A desires to.transmit to an idleone of the printers 201 and 202. The calling party initiates thecall by closing key 245 which establishes a circuitthrough conductor 266 for energizing relay 211;' The operation of relay 211 connects ground through the lowermost armature o1 relay 214, uppermost armature. of relay 211, and conductor 212 to the segment 213 upon which the brush of switch S rests when printer201 is idle. In this connection it must be borne in mind that, the segment 213 can be grounded only when a set of two conditions concur; first, that the relay 211 is energized, and second, that the'relay 21 1 is not energized or when a similarrelationship exists between the cuit for energizing the stepping magnetv 217.

This circuit maybe traced from the grounded contact 213, the brush of selector switch S, conductor 216, inner upper armature of .relay 215,

conductor 225 and back contact, armature and windingof relay 217 to battery. Stepping relay 21'? opens and closes the circuit just mentioned, thereby steppingthe selector brushes in unison as long as the brush of the switch S is connected to a segment which is connected to ground. As the brush of switch Sfpass'es over the segments associated with different outlying stations the brush may. find some segments grounded because the outlying station is idlev I at the selector switch, and the switches in the 2 ing circuit for itself extending from battery S and S,

bank 210 cease stepping. The brushes of all the selector switches are now resting upon their a segments. Relay 215 is thereby energized in the following circuit: Battery 218,,upperwinding'. of relay 215, brush of selector'switch M, a segment, conductor 219, break contact226 of relay 214, winding of relay 214, conductor 223, and

make contact and inner lower armature of relay 211 to ground. i

Relay 214 is energized, and establishes a lock- 222', through the inner upper armature and winding of relay 214, conductor 223, make contact and inner lower armature of relay 211 to ground.

During the time that relay 214 remains energized, its lowest armature maintainsaground connection to the a segments of the switches ping on the a segments. I

The circuit which extended through the upper winding of relay 215 is broken at the contact" 226, but before this circuit breaks, the lower winding of relay215 establishes a locking circuit extending from battery 218, through both windings of. 1'elay215 in seriesj'lower armature of. relay 215, winding of relay 224, brush of selector switch TC, segment a, conductor 221, and inner lower armature of relay 211 to ground... Relay 215 in operating releases motor control relay 2'70 therebystarting the motor 271, and also con nects the receiving printer201 through the uppermost armature of relay 215 and the brush of selector switch L to thetransmission line 262. The calling party at station A may now transmit in the usual manner by means of the transmitter 241 which is connected in a series circuit with the receiving printer 201 at the centraloflice-C.

The energizing of relay 224 connects the brush of the transfer switchT to the segment 213 of selector switch S. All of the off-normal segments of transfer switch T are connected together with a segment .228 situated on one of the selectors in the bank 220, and corresponding in function to the segment 213. a

Selecting the second printer-Fig. 2

Assume that station B desires to transmit during the time that station A is connected to the receiving printer 201. The switch 345 at station B is depressed thereby operating relay 311. The latter relay connects ground through its upper most armature and contact to the segment 213 in thebank 210. That segment is now disassociated with the brush 8 and the grounding of segment 213 does not therefore have any effect upon the operation of the bank of selectors 210. The segment213 is now connected through the 'deenergization of relay 211.

thereby preventing the selectorbrushes in any bank other than 210 from stop;

armature. of relay 224 and the'selectorswitch T to the segment 228 on the selector switch S in the bank 220.

The operation'of the bank of selectors 220 is similar to the operationo'f the bank 210. The a and b segments for the switch L-. are always connected to corresponding segments of the switch L. The same is true of the corresponding segments on selectors TC and TC, and S and S; When the segment 228 is grounded the stepping magnet 237 commences to step the selector brushes in bank 220 in the same manner that the selecting magnet 217 steps the switches of bank 210. Thus, the printer 341-342 at station B is connected through the second bank of selectors 220 to the receiving printer 202 at the main or central station.

.If desired a message register 233 may be connected to the selector switch-T to indicate the number of times that the last bank. of selectors 220 operate to connect the last printer 202 to an incoming call. The message register 233 is connected to all segments but one of the switch T, whereby the register will be operated whenever the selector switches, of the bank, 220 step from the normal position.

Calling station A disconnects 'l ihen the party at station Alias finished his message, he releaseskey 245 thereby causing the s The latter in releasingdeenergizes relays 224 and 215. The release of relay 215 restores the motor 271 and the printer. to their normal conditions and the motor 271 comes to rest. The-release of relay '211 also causes-the breaking of the circuit extending throughrelay 214. The latter relay releases, thereby stopping the motor 243 at calling station A. .The releasing of relay 211 also restores ground to the contact segment a of selector switch S whereupon the stepping mag- .net 217 isreenergized and commences to step until the selectors in bank 210 have reached their normal position, and the brush of selector S rests upon segment 213.

Flashing circuit ,say station A is connected to' any receiving printer at station C the relay 214 will be energized, thereby closing a circuit through the sig-. nal lamp 261. This circuit causes the lamp to 4 light continuously whereby an operator-may be "apprized of the fact that station A is connected to one of the receiving printers. In case one of the stations, say station B, attempts unsuccessbeing connected continuously to ground, as in the case of the relay 261, the lamp 361- is connected to the armatu'reof a relay 281 which successively makes and, breaks a connection to ground. The. connection between the lamp 361 and the armatureof relay 281 may be traced armature and break contact 01 relay 314, make contact of lowermost armature of relay 311, and armature of relay 281 to ground.

The winding of relay .281 is connected in a circuit which closes through. relays 311 and 31.4 to ground, Whenever relay 311 is energized and relay. 314 not energized. The connection may be tracedfrom the winding of relay ,281 through the upper inner armature of relay 311 and Iow ermost armature of relay 3l4'to ground. Connected in the same circuit is ,an interrupting device 363 for'causing the circuit through relay 281 to be opened and closed automatically.

The relay 281 is' similarly adapted to be connected through the relays 211 and 214. to the lamp 261, for flashing the lamp 261 whenever the station A makes. an uncompleted call.

In the circuit of Fig. 2, there may be other outlying stations in. addition to stations A and B. Similarly there may be other banks or" selectors intermediate banks 210 and 220.

Keys and printers may be provided to give outgoing service by the same means 4, ,4, 5,5 as shown in Fig. 1. 1 i

What is claimed is: 1

1. A signaling system comprising .a sending station, a plurality of receiving stations each provided with a signal recording device and a motor, selecting means for automatically establishing in one operation-a.connection between the sending stationand an idle one of said r reciving station whenever any one of said receiving stations is idle,.characterized by means at the sending station for controlling the starting and the stopping of the motor at the connected receiving station.

2. Ina signaling system, a signal sending station, a plurality of signal recording stations, automatic switching apparatus adapted to connect the sending station to any one of therecording stations, a line extending iromi the sending station to the switching apparatus and being normally open, and means for closing said line, characterized in this that the switching apparatus is responsive to the closing of said line to select an idle one of said recording stations. i

3. In a printing'telegraph system, a central ofiice havinga plurality of receivers,-'a plurality of outlying stations each-connected to the central oilice by atransinission line and a calling line, said transmission line being open-circuited at the central office and the calling line being open-circuited at the outlying station. when the latter is not in use, and means re sponsive to the closing of the calling line to connect the transmission line to an idle printer. 4. In a printing telegraph system, a central plurality of outlying stations each connected to the central office by a transmission line and a calling line, said central office being provided when the latter is not in use, and said selecting devices being responsive to the closing of the calling line to connect the transmission line to an idle printer.

5. A printing telegraph system as defined in claim 4 in which each selecting device, during the time its associated printer is busy, closes device to receive a "receiving printer,

oiiice having a plurality of receiving printers, a

a circuit for preparing the next idle selecting outlying .station.

' 5 6. In a printing telegraph system, an idle printer finder comprising a central ofiice, a plurality of outlying stations each connected to thecentral office by aline which isnormally oplen-circuited at the central office, said central succeeding call from another .OfilCB'hitl/lllf, a pluralityof printers, a group of relays associated with each of said printers, e ach of'relays having means for establishing a connection between any one of said lines and the: printer associated with the group, and switching means "each'outlying station for operating an idle one of saidgroups'to establish such connection.

'7. In a'printing telegraph system, a central office having a plurality of receivingprinters, a motor and a selecting device associated with each one of saidreceiving printers, a plurality of outlying stations eachconnected to the cen tral office by a transmission line and a calling to an idle one of said printers, and having means i for starting the motor for the receiving: printer when the latter is connected to one of the transmission lines. V

8; A printing telegraph systemas definedin claim Tin which each outlying station is provided'with motorwhich is startedby means common to the means'for starting the motor for the receiving printer.

' 9.'In a printing telegraph system, acentral oiiice having a plurality of receiving printers, a plurality of outlying stations each connected to thejcentral office by a transmission line, the transmission line beinggnormally open-circuited at the central office, said central office having a bank of selector switches associated with each 7 one selector switch being adapted to connectingtransmission line with the associated receiving printer, the establishment of such connection being under the control ofthe calling outlying station, and another selector" switclrbeing adapted toprepare the nextidle selector bank to connect its associated receiving 1 center with the next callingoutly'ing station. '10. A printing telegraph system as defined in claim 9 which includes further a message register and means for energizing the message register each time that all'banks' of selector switches and all receiving printers'are in use) 11. In a printing telegraph system, a central office having a plurality of. receiving printers, a plurality of outlying stations, each provided with a printer and a motor-therefor, the printer being connected to the central office by a transmission line, the central ofiice having a pair of relays associated with each outlying station and having also selecting apparatus, the first relay of each pair being operable under the control of a calling outlying station and adapted to cause the selecting apparatus to establish adapted to. be energized in response to the oper-' 1.13. In aprinting telegraph system as defined in claim 11, a flashing circuit for indicating an unsuccessfulcall, said fiashingcircuit being adapted to cause an intermittent current to flow through the lamp, and said flashing circuit being' adaptedto be 'c'losed when the first. relay of a pair, of relay'sis operated and the second relay is non-operated.

14; A telegraph signaling system comprising a plurality of outlying stations each station being provided with telegraphicinstrumentalities operated by amotor, a central station comprising a plurality of receivers connectable with said instrumentalities over 4 circuits, selecting means controllable from any one ofsaid outlying stations for selecting an idle one of said receivers whenever any of said receivers is idle and establishing a connection 'therebetween and said instrumentalities, and means responsive to the establishment of such connection for starting the motor at the station. I

15. A system as defined in claim 14 in which a line circuit extending through said-instrumentalities and to at least one of said receivers is normally open when idle.

16. A telegraph signaling system comprising a plurality of outlying calling stations each provided with a transmitter and a motor therefor, a central station comprising a plurality of re ceivers separated fromithe calling station, a circuit changing device at said calling station, means at said central station operative under the influence of said device upona calling actuation thereof being made for selecting an idle one of said receivers and connecting it to the transmitter of said calling outlying station in signal transmitting relation whenever any of said receivers is idle, and means also operative under the influence of said device for disconnecting said selected receiver without disturbing the condition of operation of other of said receivers. l 1

1-7. A system in accordance with claim 16 wherein a single operation of said circuit changing device sets into operation means for selecting an idle one of said receivers and a single operation restores the selected receiver to non-signaling condition. a

18. In a telegraph system, a central station having a plurality of transmitters and a plurality of receivers, a'plurality of outlying stathe I tions, lines associated with said outlying stations and terminating at said central station, means whereby an operator at the central station may selectand connect a central station transmitter to any desired idle outlying station receiver and may start the motors of both said transmitter and said receiver and may thereafter stop both said motors, and means whereby an operator at an outlying station may connect'his local station transmitter to one of the central station means whereby an operator at an outlying station may connect his transmitter to one of the receiving printers at the central station if any of said receivingprinters be idle and may cause both .his own transmitter motor and the motor of said connected receiving printer to start,

. means for causing both said motors to stop Whenever said operator disconnects his transmitter, means whereby an operator at said central station may connect a transmitter at the central station to the receiver of any desired outlying station which is idle and may start the motor of his centralstation transmitter and that of the receiver' at the outlying station to which the transmitter is conneotedgand means for stopping said two last-mentioned motors when the central station operator disconnects thetransmitter from the outlying receiver.

20. In combination, a telegraph station having atransmitting device and a telegraph receiving printer, a line terminating at said station, a plurality of other telegraph stations. each equipped with printing telegraph transmitters and printing telegraph receivers associated with said line, said other stations being remote from said firstmentioned station, means whereby an operator at any of said other'stations may start and stop the motor of his own station and that of said first-mentioned station when said first-mentioned station is otherwise idle and may transmit telegraph messages from his local printer to the receiver of said first-mentioned station, and means whereby an operator at said first-mentioned station may cause the starting of his own motor and that of an idle one of said other stations in I one operation if any of said other stations be idle, may transmit a message from his local transmitter to the receiver of said connected said stations at the conclusion of said message.

DONALD B. PERRY. 

